Spring driven adjustable oral syringe

ABSTRACT

Embodiments disclosed herein generally describe a medication delivery system. The medication delivery system includes a barrel, a plunger assembly, a dosage selection device, and a force producing element. The plunger assembly is disposed within the barrel. The force producing element can force the plunger assembly from the barrel. The user can select one or two or more dosages with a dosage selection device. The user selects the dosage; then the medication delivery system delivers the same dosage repeatedly. Further, with the force producing element, the user need only depress the plunger assembly into the barrel and does not need to extract the plunger assembly. This allows the user to use only one hand with the medication delivery system.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a Divisional of U.S. application Ser. No.12/350,001, filed Jan. 7, 2009 which said application claims the benefitof priority to U.S. Provisional Application No. 61/010,481 filed Jan. 8,2008, the entire disclosure of each of which are hereby incorporatedherein by reference.

FIELD OF THE INVENTION

Medical devices and, more specifically, medicine measuring devices.

BACKGROUND

Parents and caregivers generally have four types of devices to measureout and dispense liquid medication including a manual syringe with agraduated scale printed on the barrel, a “spoon” that is a test tubeshape with a spout to drink from, again with a graduated scale on theside, a bulb-type suction syringe with a graduated scale on the barrel,and a cup with graduated scale. These devices require utilizing an oftenhard to see and difficult to read graduated scale to determine how muchmedicine is being taken or poured into the device and thereforeadministered. Caregivers, trying to get just the right amount, often endup pouring medicine back into the medicine bottle, contaminating themedicine. The FDA has sighted overdose of cough and cold medications,especially in very young children, as a common hazard.

BRIEF SUMMARY

Embodiments disclosed herein would alleviate the potential hazard ofoverdosing liquid medication by having a large, easy to read, colorcoded display stating the dosage. The user can determine the amountbefore taking up the liquid. This novel apparatus allows the user toconfidently administer a dosage easily and accurately without grapplingwith the small print of the graduated scale. It would also, utilizing aspring, take in the exact amount of liquid, alleviating the issue ofcontamination of the medicine in the bottle, and allow the user to drawin the liquid with one hand. In embodiments, the labeling on the devicehas multiple visual clues as to the chosen dosage so that not only doesthe window display the written amount, but each different amount has acolor coded bar whose length is proportional to the dosage amount,therefore alleviating many typical errors in reading the closing device.

BRIEF DESCRIPTION OF THE DRAWINGS

The embodiments of the present disclosure are described in conjunctionwith the appended figures:

FIG. 1A is an exploded isometric view of an embodiment of a medicationdelivery system;

FIG. 1B is an isometric view of an embodiment of a medication deliverysystem;

FIG. 2A-E are two-dimensional and cut-away views of embodiments of amediation delivery system;

FIGS. 3A-D are two-dimensional views of embodiments of a shaft in amediation delivery system;

FIG. 4A is a flow diagram of an embodiment of a method for administeringmedication with a mediation delivery system;

FIG. 4B is a flow diagram of an embodiment of a method for selecting adosage with a mediation delivery system;

FIG. 4C is a flow diagram of an embodiment of a method for siphoningmedication with a mediation delivery system;

FIG. 5 is a flow diagram of an embodiment of a method for constructing amediation delivery system; and

FIG. 6A-C are three-dimensional and partial cut-away views ofalternative embodiments of a mediation delivery system.

FIG. 7A-C are three-dimensional and partial cut-away views of otheralternative embodiments of a mediation delivery system.

In the appended figures, similar components and/or features may have thesame reference label. Further, various components of the same type maybe distinguished by following the reference label by a dash and a secondlabel that distinguishes among the similar components. If only the firstreference label is used in the specification, the description isapplicable to any one of the similar components having the same firstreference label irrespective of the second reference label.

DETAILED DESCRIPTION

The ensuing description provides exemplary embodiment(s) only and is notintended to limit the scope, applicability or configuration of thepossible embodiments. Rather, the ensuing description of the exemplaryembodiment(s) will provide those skilled in the art with an enablingdescription for implementing an exemplary embodiment. It should beunderstood that various changes may be made in the function andarrangement of elements without departing from the spirit and scope ofthe possible embodiments as set forth in the appended claims.

Embodiments presented herein provide for a medication delivery device.The medication delivery device can be a syringe allowing a user toselect a dosage from several dosages. The dosage is presented to theuser in visual form on the syringe. Once selected, the syringe providesthe selected dosage. In further embodiments, the syringe also includes aspring that creates a force on the plunger of the syringe. The appliedforce can cause the syringe to return to an initial position. Thus, theuser need only push the plunger into the barrel of the syringe. Thus,the user need only use one hand to operate the syringe, and the syringecan repeatedly administer the same dose without further effort by theuser.

A medication delivery system 100 is shown in FIGS. 1 and 2A-2E. Themedication delivery system 100 can include a barrel assembly 108 and aplunger assembly 102. The medication delivery system 100 can alsoinclude a dosage selection device that can be coupled to or incorporatedinto the barrel assembly 108 and/or the plunger assembly 102. The dosageselection device can allow the user to select one of two or more dosagesfor delivery of a medication or liquid. Several embodiments of themedication delivery system 100 are possible, and one embodiment of themedication delivery system is shown in FIGS. 1 and 2A-2E.

The medication delivery system 100, in embodiments, is a syringe asshown in FIGS. 1 and 2A-2E. The medication delivery system 100 mayhereinafter be referred to as a syringe. However, the variousembodiments are not limited to just syringes or the embodiments shown inthe figures as one skilled in the art will see other possibleembodiments. The barrel assembly 108 can comprise a barrel 110. Thebarrel assembly 108 may be formed from a rigid material, for example, aplastic, metal, glass, or other material.

The barrel 110 can include a distal end 132 and a proximal end 134. Atthe distal end 132 of the barrel 110, a nozzle 126 can be formed intothe barrel 110 and an orifice may be formed in the end of the nozzle126. In embodiments, the barrel assembly 108 also includes a barrel cap112. The barrel cap 112 can have a detent 132 formed into the barrel cap112. Further, the barrel cap 112 can include a hole 140 that allows theplunger assembly 102 to pass through the barrel cap 112. The barrel cap112 can be attached to the proximal end 134 of the barrel 110 after thefinal assembly. To attach the barrel cap 112, the barrel cap 112 can bescrewed onto threads 124 formed in the proximal end 134 of the barrel110. In other embodiments, the barrel cap 112 may be adhered ormechanically fastened to the barrel 110 through other means. The barrelcap 112 can include a flange 142 formed circumferentially around an endof the barrel cap 112. Further, the barrel cap 112 can include a detent132 formed within the opening 140 of the barrel cap 112. In embodiments,the barrel cap 112 may also include a visual indicator 130 that directsthe user's attention to a dosage marking, as explained in conjunctionwith FIGS. 2A-2E. The barrel cap 112 can also have ribs 142 formedaround the exterior wall of the barrel cap 112. The ribs 142 provide atextured surface for the user to more easily grab.

The plunger assembly 102, which may also be referred to as a piston, caninclude a shaft 106, a plunger 104, and a plunger cap 109. The shaft 106and plunger cap 109 may be formed from a rigid material, for example, aplastic, metal, or glass. The plunger 104 may be coupled to or attachedto the distal end 136 of the shaft 106. The plunger cap 109 can becoupled to or attached to the proximal end 138 of the shaft 106. Afterassembly, the plunger assembly 102 may be, at least partially, disposedwithin the barrel 110. In embodiments, the plunger 104 may be formedfrom a semi-rigid material, for example, a rubber material. The plunger104 may be formed as to contact the inner walls of the barrel as theplunger assembly 102 is moved within the barrel 110. The plunger 104 maybe formed so as to create an airtight seal within the barrel 110allowing the syringe 100 to create a vacuum. The vacuum allows themedication delivery system 100 to siphon medication from a bottle orother receptacle as the plunger assembly 102 is pulled from the barrel110.

The shaft 106 can have two or more lengthwise ribs 116 a, 116 b, and/or116 c formed along the longitudinal axis of the shaft 106. One or moreradial ribs 120 a and/or 120 b may be formed between the two or morelengthwise ribs 116 a, 116 b, and/or 116 c. Each radial rib 120 a and/or120 b may be formed at a predetermined location along the longitudinalaxis of the shaft 106 between the distal end 136 and the proximal end138 of the shaft 106. The predetermined location is determined by theamount of dosage to be siphoned into the barrel when the plungerassembly 102 is pulled from the barrel. The medication delivery system100 can siphon a predetermined volume of medicine into the barrel 110 bypulling plunger 104 from the distal end of the barrel. When the plungerassembly 102 reaches a predetermined distance from the distal end of thebarrel, one of the radial ribs 120 a and/or 120 b will contact thedetent 132 and stop the plunger assembly 102 from being pulled furtherfrom barrel 110. Each lengthwise rib 116 a, 116 b, or 116 c can have anindention 118 a, 118 b, or 118 c formed within the lengthwise ribs 116a, 116 b, and/or 116 c. The plunger assembly 102 can rotate within thebarrel 110. To allow the lengthwise ribs 116 a, 116 b, and/or 116 c torotate, the indention 118 a, 118 b, or 118 c allows the detent 132 topass by the lengthwise rib 116 a, 116 b, or 116 c. In other positions,the detent 132 rides within the channel for between two of thelengthwise ribs 116 a, 116 b, and/or 116 c. Thus, once a dosage is set,that dosage is maintained until the user sets the syringe 100 foranother dosage.

The syringe 100 can also include a force producing element 114. Inembodiments, the force producing element 114 produces a force thatextracts the plunger assembly 102 from the barrel 110. Thus, the plungerassembly 102 can be manually pushed into the barrel 110, and the forceproducing element 114 can push the plunger assembly 102 from the barrel110. The force producing element 114, in embodiments, is a coil spring.However, the force producing element 114 can be a leaf spring, ahydraulic system, or other device that can produce a force as describedherein. The force producing element 114 can be made from any semi-rigidmaterial that has good tensile strength and will compress anddecompress, for example, a metal.

In embodiments, the medication delivery system 100 further includes awindow 128 formed into the barrel 110. The window 128 can be a clear ortransparent section of the barrel 110 that provides a view to the shaft106 of the plunger assembly 102. The barrel 110 may be painted or coatedand the painting or coating may be missing from the window 128. In otherembodiments, the barrel 110 is formed from a first material that isnon-transparent and the window 128 is formed from a second transparentmaterial. The barrel 110 may also be formed completely from a clearmaterial, and the window 128 is shown by one or more markings.

The window 128 allows a user to see indicia 144 shown on the shaft 106of the plunger assembly 102. As shown in FIGS. 3A-3D, the shaft 106 hasfour sections formed by pairs of the lengthwise ribs 116 a, 116 b,and/or 116 c. The shaft 106 can have more or fewer sections than thoseshown. Indicia 144 are marked in a section of the shaft 106 between twolengthwise ribs 116 a, 116 b, and/or 116 c. A radial rib 120 is formedbetween each of the pairs of the lengthwise ribs 116 a, 116 b, and/or116 c. The radial rib 120 is located at a predetermined distance alongthe shaft 106 such that the syringe will deliver the dosage indicated bythe indicia 144 when that section of the shaft 106 is selected.

The indicia 144 can be one or more markings describing the predeterminedvolume that medication delivery system 100 will siphon when the plungerassembly 102 is pulled from the barrel 110. The indicia may be a word ormeasure, for example, “1 Tsp” as shown in FIG. 3B. The indicia 144 mayalso be a bar or other visual marking indicative of the predeterminedvolume. For example, one bar may be longer than another bar, as shown inFIGS. 3A-3D, to indicate that the volume is greater. In otherembodiments, the indicia are color coded. For example, bar 144 a isgreen, bar 144 b is blue, bar 144 c is red, and bar 144 d is yellow. Thecolors can be part of a marking system as known in the industry. Eachcolor can represent a predetermined dosage, e.g., green may represent avolume of 2 teaspoons or a color that is red may represent a volume of 1teaspoon.

A method 400 for administering a dosage of medicine with the medicationdelivery system 100 is shown in FIGS. 4A-4C. The method 400 will beexplained in conjunction with FIGS. 1-3D. Generally, the method beginswith a start operation 402 and terminates with an end operation 414. Auser determines the dosage needed in step 404. The user can read theinstructions on the label of the medication. The instructions may bepresented by a doctor if the medication is prescription medication or bya company if the medication is over-the-counter. In embodiments, theinstructions include a color-coded amount on the label. For example,green indicia may represent a volume of 2 teaspoons or red indicia mayrepresent a volume of 1 teaspoon.

A user sets the dosage in step 406. The user can set the dosage byadjusting the syringe 100 to the proper dosage. For example, the useradjusts the position of the plunger assembly 102 within the barrelassembly 108 until the determined dosage is selected. An embodiment of amethod 416 to select a dosage is shown in FIG. 4B.

Medication is siphoned into the medication delivery system 100 in step408. The user can insert the nozzle 126 of the medication deliverysystem 100 into a receptacle holding a fluid medication. The user maythen pull the plunger assembly 108 from the barrel 110 to draw the fluidinto the barrel 110. In embodiments, the movement of the plungerassembly 108 being extracted from the barrel 110 creates a vacuum thatdraws the fluid into the barrel 110. A method 428 for siphoningmedication is shown in FIG. 4C.

The user can administer medication in step 410. The user can insert thenozzle 126 into the mouth of the patient (the user and patient may bethe same person). The user can then depress the plunger assembly 102into the barrel 110. The plunger 104 may push the medication from thebarrel 110 through the orifice in the nozzle 126 and into the patient'smouth. The act of depressing the plunger assembly 102 can compress theforce producing assembly 114 (e.g., compress the coil spring).

A user may need to deliver another dose of medication to either anotherpatient or to the same patient. The user may then determine if anotherdose is needed in step 412. If another dose of medication is needed, themethod 400 flows YES to repeat steps 408 and 410. In embodiments, theuser need not determine or set another dosage. With the medicationdelivery system 100 already set to provide a determined dose, the userneed only siphon the medication again. The user siphons thesubstantially similar amount of medication. In other embodiments, theuser may need to determine a new dose and repeats steps 404 through 410.If the user does not need to administer another dose, the method flowsNO to end 414.

A method 416 for setting a dosage is shown in FIG. 4B. The method 416will be explained in conjunction with FIGS. 1-3D. Generally, the methodbegins with a start operation 418 and terminates with an end operation426. A syringe 100 can be in a first “neutral position” as shown in FIG.2A. A user depresses the plunger assembly 102 into the barrel 110 instep 420. The user can depress the plunger assembly 102 by pushing theplunger cap 109 towards the barrel 110. The user stops depressing theplunger assembly 102 when the plunger assembly 102 is substantiallyoriented in the barrel 110 as shown in FIGS. 2B and 2C. Here, the shaft106 is disposed within the barrel 110. The plunger 104 may besubstantially near the distal end 132 of the barrel 110. Moresignificantly, the indentions 118 in the lengthwise ribs 116 aresubstantially aligned with the detent 132 in the barrel cap 112 as shownin FIG. 2C.

The user rotates the plunger assembly 102 until the determined dosage isselected in step 422. While the plunger assembly is depressed as shownin FIGS. 2B and 2C, the user rotates the shaft 106 of the plungerassembly 102 within the barrel 110. The user can rotate the shaft 106along the longitudinal axis of the shaft 106 by turning the plunger cap109 either clockwise or counterclockwise in respect to the longitudinalaxis. The lengthwise ribs 116 also rotate within the barrel 110.Further, the lengthwise ribs 116 pass by the detent 132 because theindentions 118 move past the detent 132. The user selects theappropriate dosage by viewing the dosages indicia 144 (as shown in FIGS.3A-3D) through the window 128. For example, dosage indicia 144 c areshown through the window 128 in FIG. 2B. The indicator 130 directs theuser's attention to the window 128. If the indicia 144 for thepredetermined dosage is shown in the window 128, the user has selectedthe predetermined dosage.

The user then releases the plunger assembly 102 in step 424. The usercan stop depressing the plunger assembly 102 into the barrel 110. Theforce producing element 114 (e.g., the coil spring) produces a force onthe plunger assembly 102. The force pushes the plunger assembly 102 fromthe barrel 110. In embodiments, the force is produced by the spring 114attempting to return to a decompressed state. The force producingelement 114 continues to push the plunger assembly 102 from the barrel110 until the radial rib 120 associated with the set dosage contacts thedetent 132, as shown in FIG. 2E. The position of the plunger assembly102 in the barrel 110, as shown in FIGS. 2D and 2E, becomes the new“neutral position” for the medication delivery system 100. The neutralposition is the position of the plunger assembly 102 within the barrel110 without the user putting any force upon the medication deliverysystem 100. The volume 146 within the barrel 110 is the volume 146associated with the determined dosage. The syringe 100 may thus siphonand administer the selected dosage every time the syringe 110 is useduntil the user selects a new dosage. Further, the user can use a singlehand to depress the plunger assembly 102 to siphon the medication,allowing the force producing element 114 to extract the plunger assembly102 from the barrel 110. Thus, the syringe 100 is easier to use than atypical syringe. In alternative embodiments, the medication deliverysystem 100 does not include a force producing element 114, and the usermust pull the plunger assembly 102 from the barrel.

A method 428 for siphoning the medication with the medication deliverysystem 100 is shown in FIG. 4C. The method 428 will be explained inconjunction with FIGS. 1-3D. Generally, the method begins with a startoperation 430 and terminates with an end operation 438. The user pushesthe plunger assembly 102 into the barrel 110 after selecting the dosagein step 432. The user can push the plunger cap 109 towards the barrel110 to depress the plunger assembly 102. By depressing the plungerassembly 102, the user also compresses or loads the force producingelement 114.

The user can insert the nozzle 126 of the medication delivery system 100into the medication in step 434. The medication may be in a bottle orother receptacle. Thus, the nozzle 126 is either long enough to besubmerged into the medication or the barrel 110 has a small enoughoutside diameter to be inserted through the orifice of the bottle. Theuser then releases plunger assembly 102 in step 436. The user can reducethe amount of force produced on the plunger assembly 102 allowing theforce producing element 114 to push the plunger assembly 102 from thebarrel 110. The plunger 104 contacts the inner walls of the barrel 110and creates an airtight seal within the barrel 110. Moving the plungerassembly 102 from the barrel 110 creates an increased volume 146 withinthe barrel. The syringe 100 creates a decrease in pressure within thebarrel 110. The decreased pressure or vacuum draws the medication fromthe bottle and into the barrel 110 until the volume 146 is filled withthe medication.

A method 500 for assembly a medication delivery system 100 is shown inFIG. 5. The method 500 will be explained in conjunction with FIGS. 1-3D.Generally, the method begins with a start operation 502 and terminateswith an end operation 526. A manufacturer forms a plunger 104 in step504. Forming any component described herein can be a process tomanufacture the component, such as injection molding, milling, or otherprocess as known in the art. The manufacturer forms a shaft 106, withlengthwise ribs, radial ribs, indentions, etc. The manufacturer attachesthe plunger 104 to the distal end 136 of the shaft 106 in step 516. Inembodiments, the plunger 104 is formed around a tab or other protrusionformed in the distal end 136 of the shaft 106. In other embodiments, theplunger 104 is glued or adhered to the distal end 136 of the shaft 106.The plunger 104 may also be mechanically attached to the shaft.

The manufacturer can form a barrel 110, with a nozzle 126, a window 128,and optionally, threads 124 in step 508. The manufacturer inserts theplunger 104 and shaft 106 into the barrel 110 in step 518. Themanufacturer forms a barrel cap 112 in step 510. The barrel cap 112 canthen pass the barrel cap 140 over the shaft 106. Then, the barrel cap112 can be attached to the barrel 110 in step 520. In embodiments, thebarrel cap 112 can be threaded onto the threads 124 formed in the barrel110. In other embodiments, the barrel cap 112 can be adhered ormechanically fastened to the barrel 110.

The manufacturer can form a spring or other force producing element 114in step 512. The spring 114 can be placed over the shaft 106 in step522. A plunger cap 109 can then be formed in step 514. The plunger cap109 may then be attached to the shaft 106 to form the plunger assembly102 in step 524. The plunger cap 109 may have a flange and an orificeaccepting a protrusion formed in the proximal end 138 of the shaft 106.Thus, the plunger cap 109 can be mechanically fastened to the shaft 106.In other embodiments, the plunger cap 109 can be threaded onto the shaftor adhered to the shaft 106.

An alternative design for the medication delivery system 600 is shown inFIGS. 6A-6C. Here, the medication delivery system 600 includes a barrel602. The barrel 602 can include a nozzle 604 at the distal end 610 ofthe barrel 602 and threads 608 in the proximal end 612 of the barrel602. The barrel 602 may also include two or more indicia 606 a, 606 b,606 c, or 606 d formed around the outside circumference of the barrel602. The indicia 606 a, 606 b, 606 c, or 606 d may indicate the two ormore dosages.

The medication delivery system 600 can also include a plunger assembly614. The plunger assembly 614, similar to plunger assembly 102 (FIG. 1),can include a plunger 616, a shaft 618, and a plunger cap 622. The shaft618 can be threaded to accept a nut 624. The nut 624 can be rotatedabout the longitudinal axis of the shaft 618 to move the nut 624 betweenthe distal end 626 and the proximal end 628 of the shaft 618. The shall618 may be disposed inside a barrel cap 630 that can be attached to theproximal end 612 of the barrel 602. Thus, the plunger assembly 614 isdisposed within the barrel 602. A force producing element 632 can bedisposed around the shaft 618 and between the barrel cap 630 and theplunger cap 622.

To select the determined dosage, the user depresses the plunger assembly614 into the barrel 602 to expose the nut 624. The user then rotates thenut 624 along the shaft 618 until the plunger 616 is in line with one ofthe indicia 606. Thus, the barrel 602 may be formed of a clear materialto shown the plunger 616 within the barrel 602. The user can release theplunger assembly 614 allowing the force producing element 632 to extractthe plunger assembly 614 from the barrel 602. The force producingelement 632 continues to push the plunger assembly 614 from the barrel602 until the nut 624 contacts the inside surface of the barrel cap 620.

Another alternative design for the medication delivery system 700 isshown in FIGS. 7A-7C. Here, the medication delivery system 700 includesa barrel 702. The barrel 702 can include a nozzle 704 at the distal end712 of the barrel 702 and two or more indentions 716 a, 716 b, or 716 cformed in the proximal end 718 of the barrel 702. The barrel 702 mayalso include two or more indicia 718 a, 718 b, or 718 c formed aroundthe outside of the barrel 702 and inline or parallel with indentions 716a, 716 b, or 716 c. The indicia 718 a, 718 b, or 718 c may indicate thetwo or more dosages.

The medication delivery system 700 can also include a plunger assembly720. The plunger assembly 720, similar to plunger assembly 102 (FIG. 1),can include a plunger 722, a shaft 724, and a plunger cap 726. The shaft724 may be disposed inside the barrel 702. The plunger cap 726 may beformed with an outside wall 728 such that the outside wall 728 is formedcircumferentially around the outside of the proximal end 718 of thebarrel 702. A detent 730 is formed at a predetermined location on theinside of the outside wall 728. The detent 730 is disposed in one of theindentions 716 a, 716 b, or 716 c. A force producing element 732 can bedisposed around the shaft 718 and inside the plunger cap 726.

To select the determined dosage, the user depresses the plunger assembly720 into the barrel 702 to release the detent 730 from one of theindentions 716 a, 716 b, or 716 c. The user then rotates the plungerassembly 720 until the indicator 734 is in line with one of the dosageindicia 718 a, 718 b, or 718 c. The user can release the plungerassembly 720 allowing the force producing element 732 to extract theplunger assembly 720 from the barrel 702. The force producing element732 continues to push the plunger assembly 714 from the barrel 702 untilthe detent 730 contacts the proximal end of the selected indention 716a, 716 b, or 716 c, shown in FIG. 7B.

In further embodiments, a needle may be disposed at the end of orinstead of a nozzle 154. Further, the dosage may be selected by a doctorand set permanently so the same dosage would be given each time. Thisembodiment would prevent the user selecting the incorrect dosage. Forexample, the doctor or pharmacist would select the dosage by insertingthe plunger assembly 102 into the barrel 110 with the detent 132 betweenthe correct pair of lengthwise ribs 116. Then, the doctor or pharmacistcan complete the construction of the plunger assembly 102 by attachingthe force producing element 114 and plunger cap 109. The lengthwise ribs116 a, 116 b, and/or 116 c would not have an indention 118 that wouldallow the selection of a different dosage.

While various aspects of embodiments of the disclosure have beensummarized above, the following detailed description illustratesexemplary embodiments in further detail to enable one of skill in theart to practice the disclosure. In the description, for the purposes ofexplanation, numerous specific details are set forth in order to providea thorough understanding of the present disclosure. It will be apparent,however, to one skilled in the art that the present disclosure may bepracticed without some of these specific details. Several embodiments ofthe disclosure are described, and while various features are ascribed todifferent embodiments, it should be appreciated that the featuresdescribed with respect to one embodiment may be incorporated withanother embodiment as well. By the same token, however, no singlefeature or features of any described embodiment should be consideredessential to the disclosure, as other embodiments of the disclosure mayomit such features. Specific details are given in the description toprovide a thorough understanding of the embodiments. However, it will beunderstood by one of ordinary skill in the art that the embodiments maybe practiced without these specific details.

Also, it is noted that the embodiments may be described as a processwhich is depicted as a flowchart, a flow diagram, a data flow diagram, astructure diagram, or a block diagram. Although a flowchart may describethe operations as a sequential process, many of the operations can beperformed in parallel or concurrently. In addition, the order of theoperations may be rearranged. A process is terminated when itsoperations are completed, but could have additional steps not includedin the figure.

In light of the above description, a number of advantages of the presentdisclosure are readily apparent. For example, the syringe provides asimple way of selecting a dose of medication. Thus, the chance ofselecting and administering the wrong dose is reduced. Further, thesyringe will provide the same dosage repeatedly without the user havingto measure a second or subsequent dose. Still further, with the forceproducing element, the user can use the syringe with one hand.

It will be apparent to those skilled in the art that substantialvariations may be made in accordance with specific requirements. Forexample, different arrangements of components or materials might also beused. While the principles of the disclosure have been described abovein connection with specific apparatuses and methods, it is to be clearlyunderstood that this description is made only by way of example and notas limitation on the scope of the disclosure.

What is claimed is:
 1. A method for selecting a dose of medication, themethod comprising: compressing a plunger assembly into a barrelassembly, wherein the plunger assembly includes a shaft having a distalend and a proximal end; rotating the plunger assembly within the barrelassembly to select a dosage by viewing visual indicia indicative of thedosage; inserting the barrel assembly into a fluid; releasing theplunger assembly such that a force producing element produces a force onthe plunger assembly; the force producing element extracting the plungerassembly from the barrel assembly until a radial rib contacts a detenton a barrel cap assembly, wherein the radial rib is disposed between twoor more lengthwise ribs; wherein the radial rib is disposed in at leastone portion of a circumference of the shaft, but not extending along afull circumference of the shaft; and wherein the radial rib is disposedlengthwise on the shaft between the distal end and the proximal end ofthe shaft to provide a predetermined volume of the fluid in the barrelassembly when the radial rib contacts the barrel cap assembly; andsiphoning the fluid into the barrel assembly as the plunger assembly isextracted.
 2. The method as defined in claim 1, wherein compressing theplunger assembly includes pushing a plunger cap toward the barrelassembly to compress the force producing element.
 3. The method asdefined in claim 1, wherein compressing the plunger assembly includescompressing the plunger assembly into the barrel assembly until anindention, formed within the two or more lengthwise ribs, is in linewith the detent.
 4. The method as defined in claim 1, wherein rotatingthe plunger assembly includes rotating the two or more lengthwise ribswithin the barrel assembly by rotating the detent by at least oneindention formed within the two or more lengthwise ribs.